Myth: People with autism are just like Rainman.
Autism varies greatly from person to person. If you know one person with autism, you only know one person with autism. That person will have completely different characteristics than the next autistic person you meet. For example, my son could not count toothpicks off the floor in a matter of seconds, but he can remember the smallest imperfection in a building from years ago.
Source: Autism Speaks